Quick answers
- Which hospitals does Gregory Granzeier work at?
- Medicare's official clinician data lists Gregory Granzeier at 2 hospitals: CGH Medical Center and Javon Bea Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Gregory Granzeier see patients?
- Medicare's clinician data lists 3 practice locations, including Sterling, IL, Rockford, IL and Roscoe, IL. Call before your visit to confirm the address.
- What is Gregory Granzeier's specialty?
- Medicare lists Obstetrics/Gynecology as the primary specialty.
- Does Gregory Granzeier accept Medicare assignment?
- Yes. Medicare's clinician data says Gregory Granzeier accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- What is the phone number for Gregory Granzeier?
- (815) 625-4790, as listed in official Medicare / NPI Registry data.
- What is Gregory Granzeier's NPI number?
- 1134239320. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Gregory Granzeier works
Medicare's Facility Affiliation Data lists Gregory Granzeier at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- CGH Medical CenterSterling, IL · Acute Care Hospital · CCN 140043
- Javon Bea HospitalRockford, IL · Acute Care Hospital · closed, according to its website · CCN 140239
Practice locations
Addresses where Gregory Granzeier is enrolled with Medicare (CMS data updated 2026-10-02).
- 101 E Miller RdSterling, IL 61081 (815) 625‑4790
- 2400 N Rockton AveRockford, IL 61103 (815) 971‑3507
- 5000 Prairie Rose DrRoscoe, IL 61073 (815) 971‑2000
Group practices
Medicare enrollment lists Gregory Granzeier as a member of these groups (CMS data updated 2026-10-02).
- Rockford Health Physicians521 clinicians in the group
- CGH Medical Center197 clinicians in the group
Specialties
- Obstetrics/Gynecologyprimary
Other OB-GYNs in Sterling
Clinicians with the same Medicare primary specialty in Sterling, IL — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | New York College Of Osteo Medicine Of New York Institute Of Technology |
| Graduation year | 1991 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1134239320 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians